// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CC_RESOURCES_UI_RESOURCE_BITMAP_H_
#define CC_RESOURCES_UI_RESOURCE_BITMAP_H_

#include <stdint.h>

#include <memory>

#include "base/memory/ref_counted.h"
#include "cc/base/cc_export.h"
#include "third_party/skia/include/core/SkBitmap.h"
#include "third_party/skia/include/core/SkCanvas.h"
#include "third_party/skia/include/core/SkPixelRef.h"
#include "ui/gfx/geometry/size.h"

class SkBitmap;

namespace cc {

// A bitmap class that contains a ref-counted reference to a SkPixelRef that
// holds the content of the bitmap (cannot use SkBitmap because of ETC1).
// Thread-safety (by ways of SkPixelRef) ensures that both main and impl threads
// can hold references to the bitmap and that asynchronous uploads are allowed.
class CC_EXPORT UIResourceBitmap {
public:
    enum UIResourceFormat {
        RGBA8,
        ALPHA_8,
        ETC1
    };

    gfx::Size GetSize() const { return size_; }
    UIResourceFormat GetFormat() const { return format_; }
    bool GetOpaque() const { return opaque_; }
    void SetOpaque(bool opaque) { opaque_ = opaque; }

    // Draw the UIResourceBitmap onto the provided |canvas| using the style
    // information specified by |paint|.
    void DrawToCanvas(SkCanvas* canvas, SkPaint* paint);

    // User must ensure that |skbitmap| is immutable.  The SkBitmap Format should
    // be 32-bit RGBA or 8-bit ALPHA.
    explicit UIResourceBitmap(const SkBitmap& skbitmap);
    UIResourceBitmap(const gfx::Size& size, bool is_opaque);
    UIResourceBitmap(sk_sp<SkPixelRef> pixel_ref, const gfx::Size& size);
    UIResourceBitmap(const UIResourceBitmap& other);
    ~UIResourceBitmap();

    // Returns the memory usage of the bitmap.
    size_t EstimateMemoryUsage() const
    {
        return pixel_ref_ ? pixel_ref_->rowBytes() * size_.height() : 0;
    }

private:
    friend class AutoLockUIResourceBitmap;

    void Create(sk_sp<SkPixelRef> pixel_ref,
        const gfx::Size& size,
        UIResourceFormat format);

    sk_sp<SkPixelRef> pixel_ref_;
    UIResourceFormat format_;
    gfx::Size size_;
    bool opaque_;
};

class CC_EXPORT AutoLockUIResourceBitmap {
public:
    explicit AutoLockUIResourceBitmap(const UIResourceBitmap& bitmap);
    ~AutoLockUIResourceBitmap();
    const uint8_t* GetPixels() const;

private:
    const UIResourceBitmap& bitmap_;
};

} // namespace cc

#endif // CC_RESOURCES_UI_RESOURCE_BITMAP_H_
